AUGUSTA (AP) — An autopsy has determined that an inmate found dead in his cell at the state prison in Machiasport last week died of natural causes.

A spokesman for the medical examiner’s office told the Portland Press Herald (http://bit.ly/1gD4wKY ) that 32-year-old Phillip Kay died as a result of blood clots in both lungs.

Guards at the minimum security Downeast Correctional Facility found Kay unresponsive in his cell on Friday afternoon. He apparently died while lying in bed.

Authorities previously said the death was not a homicide and did not appear to be a suicide.

Kay was scheduled to be released next year after serving part of a 12-year sentence for an aggravated assault conviction in 2009.